From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 19 Jan 2026 11:32:47 +0000 (+0100)
Subject: 6.6-stable patches
X-Git-Tag: v5.15.198~7
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf7e48482c20d8d8093e3bf49530d074846f1177;p=thirdparty%2Fkernel%2Fstable-queue.git

6.6-stable patches

added patches:
	efi-cper-fix-cper_bits_to_str-buffer-handling-and-return-value.patch
---

diff --git a/queue-6.6/efi-cper-fix-cper_bits_to_str-buffer-handling-and-return-value.patch b/queue-6.6/efi-cper-fix-cper_bits_to_str-buffer-handling-and-return-value.patch
new file mode 100644
index 0000000000..25cb03bbad
--- /dev/null
+++ b/queue-6.6/efi-cper-fix-cper_bits_to_str-buffer-handling-and-return-value.patch
@@ -0,0 +1,35 @@
+From d7f1b4bdc7108be1b178e1617b5f45c8918e88d7 Mon Sep 17 00:00:00 2001
+From: Morduan Zang <zhangdandan@uniontech.com>
+Date: Wed, 14 Jan 2026 13:30:33 +0800
+Subject: efi/cper: Fix cper_bits_to_str buffer handling and return value
+
+From: Morduan Zang <zhangdandan@uniontech.com>
+
+commit d7f1b4bdc7108be1b178e1617b5f45c8918e88d7 upstream.
+
+The return value calculation was incorrect: `return len - buf_size;`
+Initially `len = buf_size`, then `len` decreases with each operation.
+This results in a negative return value on success.
+
+Fix by returning `buf_size - len` which correctly calculates the actual
+number of bytes written.
+
+Fixes: a976d790f494 ("efi/cper: Add a new helper function to print bitmasks")
+Signed-off-by: Morduan Zang <zhangdandan@uniontech.com>
+Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/firmware/efi/cper.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/firmware/efi/cper.c
++++ b/drivers/firmware/efi/cper.c
+@@ -162,7 +162,7 @@ int cper_bits_to_str(char *buf, int buf_
+ 		len -= size;
+ 		str += size;
+ 	}
+-	return len - buf_size;
++	return buf_size - len;
+ }
+ EXPORT_SYMBOL_GPL(cper_bits_to_str);
+ 
diff --git a/queue-6.6/series b/queue-6.6/series
index db6096457c..25be01389a 100644
--- a/queue-6.6/series
+++ b/queue-6.6/series
@@ -1 +1,2 @@
 firmware-imx-scu-irq-set-mu_resource_id-before-get-handle.patch
+efi-cper-fix-cper_bits_to_str-buffer-handling-and-return-value.patch